Morphological Variation in Indigofera Species

A morphological investigation was carried out in three Indigofera species (I. tinctoria, I. suffruticosa and I. amblyantha) with a view to identifying a set of characteristics for the individual indigo species. Distinct variation exists in stem colour; length of rachis of leaf; size, shape, colour and chlorophyll content of leaflet; number of leaflets/leaf; colour and size of flower; size, shape, colour of pod and seed. The species I. tinctoria possesses 5-11 obovate leaflets/leaf, pink flower, narrow cylindrical pod (average pod length, 28.9 mm) with slightly curved tip and cylindrical deep brown large seed (average 1000-seed weight, 5.79 g); I. suffruticosa possesses green stem with patches of reddish colour, 9-17 narrowly oblong leaflets/leaf, crimson flower, short strongly curved pod (average pod length, 14.5 mm) and cylindrical dark green small seed (average 1000-seed weight, 3.75 g); and I. amblyantha possesses 13-15 ovate to lanceolate large leaflets/leaf, cerise-violet flower with coloured tip of keel, long, thick, straight cylindrical pod (average pod length, 32.8 mm) and globose greenish yellow medium seed (average 1000-seed weight, 4.72 g).